textproduct: Quad Cities

KEY MESSAGES

- A Freeze Warning is in effect for all of eastern Iowa and northwest Illinois from Midnight until 9 AM Monday. A Frost Advisory is in effect for Scotland and Clark Counties from Midnight to 9 AM.

- Dry and warmer weather is forecast Monday through Wednesday night before cooler temperatures move into the area Friday into Saturday.

- Chances of showers and storms return Thursday into Thursday night with showers lingering across the region into next weekend.

SHORT TERM /THROUGH TONIGHT/

Issued at 241 PM CDT Sun Apr 19 2026

Deep northwest flow aloft is forecast across the region through the short term period. At the surface, high pressure will be centered near the Iowa.illinois border by 06 UTC Monday with winds becoming light and variable. This will allow temperatures to cool quickly as the sunsets and winds diminish with forecast low temperatures ranging from 26 degrees at Freeport to 34 degrees at Fort Madison. NBM forecast low temperatures show that there is a 60 to 90 percent chance of low temperatures below freezing north of a Fairfield to Galesburg line with a 30 to 60 percent chance south of that line. There is a 30 to 60 percent chance of temperatures below 28 degrees north of Highway 30 or north of a Cedar Rapids to Clinton to Sterling Rock Falls line with the highest probabilities in far northwest Illinois. There is a Freezing warning across eastern Iowa and northwest Illinois from Midnight to 9 AM Monday and Frost Advisory for Clark and Scotland Counties from Midnight and 9 AM Monday.

High pressure will shift to the east of the area after 12 UTC Monday allowing southerly winds through the day to turn to the south and begin to pull warmer air northward on Monday. It will be breezy on Monday with gusts of 15 to 25 MPH. High temperatures on Monday will be warmer and range from the mid 50s in far northwest Illinois to the upper 60s in far northeast Missouri.

LONG TERM /TUESDAY THROUGH SUNDAY/

Issued at 241 PM CDT Sun Apr 19 2026

There is broad northwest flow aloft through midweek as 500 MB ridging builds to our west as a closed 500 MB low moves into the Northern Rockies. This will allow for a warm up through Thursday. High temperatures will be in the upper 70s to lower 80s Tuesday through Thursday.

On Thursday, Synoptic models agree on ejecting a negatively tilted trough into the Plains Thursday through Friday. The surface low is forecast to stay to our north and push a cold front across the area Thursday night into Friday morning. Models show 500 to 1000 J/KG of CAPE with deep layer shear of 20 to 30 knots hinting that isolated severe storms are possible, The storm prediction center has a 15% chance of severe weather to out west on Day 5. CSU machine learning probs show a broader severe threat area across the region so stay tuned to forecasts over the next several days for any changes in the forecast or thunderstorm threats.

Models show this upper level low further occluding into southern Canada Friday into early next week placing the region in broad cyclonic flow aloft. This will bring cooler weather to the region with chances of rain showers with shortwave rotating around the upper level low moving through the region.

AVIATION /06Z TAFS THROUGH 06Z TUESDAY/

Issued at 1226 AM CDT Mon Apr 20 2026

VFR conditions are expected today as an area of high pressure remains in control of the region. Light and variable winds early this morning will turn more southerly and strengthen during the daylight hours Monday, with sustained winds around 10 to 15 knots. Some gusts to around 20 knots are also possible. Low-level wind shear is possible late in the period, but confidence on the timing remains uncertain, so will keep out of the TAFs for now.

HYDROLOGY

Issued at 1229 PM CDT Sun Apr 19 2026

The heaviest rains on Friday afternoon and evening fell in the La Moine, Pecatonica and Rock Rivers and these rivers will see the fastest responses over the next several days. The Rock River at Moline is forecast to go above major flood stage on Monday with the crest continuing through Tuesday before falling through the end of the week. Rises continue on all area rivers with longer duration rises on the Mississippi River mainly from Rock Island south.

The forecast remains dry through Wednesday night before another storm system moving across the area brings showers and storms to the area. Additional rainfall may prolong flooding depending on which basins the rain falls.

DVN WATCHES/WARNINGS/ADVISORIES

IA...Freeze Warning until 9 AM CDT this morning for IAZ040>042- 051>054-063>068-076>078-087>089-098-099. IL...Freeze Warning until 9 AM CDT this morning for ILZ001-002-007- 009-015>018-024>026-034-035. MO...Frost Advisory until 9 AM CDT this morning for MOZ009-010.